NASA orders up urgent spacewalking repairs at space station

May 22, 2017 by Marcia Dunn
This July 19, 2011 photo of the International Space Station was taken from the space shuttle Atlantis after it left the orbiting complex. NASA ordered up urgent spacewalking repairs at the International Space Station. On Tuesday, May 23, 2017, Americans Peggy Whitson and Jack Fischer will venture out to replace a data relay box that broke over the weekend. (NASA via AP)

NASA has ordered up urgent spacewalking repairs at the International Space Station.

On Tuesday, two astronauts will venture out to replace a data relay box that broke over the weekend. The job falls to the two Americans on board: commander Peggy Whitson and Jack Fischer.

The failed unit was installed not quite two months ago. It is one of two that control the station's radiators and solar panels, among other critical systems. NASA said everything is still safe in orbit because one relay box is still working, and no operations have been affected. But officials want the bad one quickly replaced, in case the good one also goes down.

Astronauts performed a similar spacewalk in 2014.

This so-called multiplexer-demultiplexer unit, or MDM, failed Saturday for unknown reasons. It was a refurbished device—containing upgraded software—and was installed at the end of March by Whitson and another astronaut. Station managers decided Sunday to do a spacewalk Tuesday morning to replace it with an on-board spare. The spacewalk should last just two hours.

Whitson and Fischer went spacewalking 1½ weeks ago. That excursion was cut short because of a leaky umbilical hose inside the space station. If Tuesday's replacement work goes well, Fischer also will hook up wireless communications antennas outside the orbiting lab, a job left undone during the May 12 spacewalk.

Six months into a 9 1/2-month mission, Whitson already holds multiple space records, including most accumulated time in space by an American and most spacewalks by a woman. This will be her 10th spacewalk and tie the record for most spacewalks by a U.S. astronaut.

Fischer arrived at the space station last month. Also on board are two men from Russia and one from France.

Explore further: The Latest: Spacewalking astronauts salvage job, back inside (Update)

More information: NASA:

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5 / 5 (2) May 22, 2017
On Tuesday, two astronauts will venture out to replace a data relay box

Well, as long as it isn't the AE-35 unit everything should be fine...right HAL?
not rated yet May 22, 2017
I don't get it why are we rushing into space, placing bodies in danger. Can't we first define an air-to-rocket tech, capable of multiple orbits and re-entry, under flight control. We'd be better of defining slingshots for launch and Small rockets and air with super light high HP motors. Try using modern technology in motor design, how many lines can we switch right in the end-bell under digital control, just torque and speed. Stator material, rotor material. juz say'n
5 / 5 (1) May 22, 2017
Tony Kushner wrote an answer to your question, hyperfuzzy:

Progress, migration, motion .. is modernity.
It's animate.
It's what living things do.
We desire.
Even if all we desire is stillness,
it's still desire for.
Even if we go faster than we should,
we can't wait.
not rated yet May 22, 2017
"....... It was a refurbished device—containing upgraded software—"

Ah the rebuilt unit failed. Any wise mechanic knows that you should always buy original factory parts if it is a hard job to replace the unit.

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